Background: Intestinal epithelial expression of antioxidants and nuclear factor kappa B (NF-κB) contribute to mucosal barrier integrity and epithelial homeostasis, two key events in the pathogenesis of inflammatory bowel disease (IBD). Genetic restoration of intestinal epithelial prohibitin 1 (PHB) levels during experimental colitis reduces the severity of disease through sustained epithelial antioxidant expression and reduced NF-κB activation. To determine the therapeutic potential of restoring epithelial PHB during experimental colitis in mice, we assessed two methods of PHB colonic mucosal delivery: adenovirus-directed administration by enema and poly(lactic acid) nanoparticle (NPs) delivery by gavage.
Methods: As a proof-of-principle to demonstrate the therapeutic efficacy of PHB, we utilized adenovirus-directed administration by enema. Second, we used NPs-based colonic delivery of biologically active PHB to demonstrate therapeutic use for human IBD. Colitis was induced by oral administration of dextran sodium sulfate (DSS) in water for 6-7 days. Wildtype mice receiving normal tap water served as controls.
Results: Both methods of delivery resulted in increased levels of PHB in the surface epithelial cells of the colon and reduced severity of DSS-induced colitis in mice as measured by body weight loss, clinical score, myeloperoxidase activity, proinflammatory cytokine expression, histological score, and protein carbonyl content.
Conclusions: This is the first study to show oral delivery of a biologically active protein by NPs encapsulated in hydrogel to the colon. Here we show that therapeutic delivery of PHB to the colon reduces the severity of DSS-induced colitis in mice. PHB may represent a novel therapeutic target in IBD.
Copyright © 2010 Crohn's & Colitis Foundation of America, Inc.